1. Technical Field
The present disclosure relates to voice coil motors, and particularly to a voice coil motor having firm structure.
2. Description of Related Art
Voice coil motors (VCMs) can be used as means of focusing in camera modules. A VCM usually includes a shell, a moving unit, a rack, and a base. The shell is made of electrically conductive materials and includes a plurality of continuous side plates to provide electro magnetic interference (EMI) shielding for the VCM. In assembling, the rack equipped with magnets is mounted to the base. The moving unit is movably received in the rack and is wound with coils. The base, the rack, and the moving unit are accommodated in the shell. The side plates sleeve outside the base such that the base can be clamped in the side plates. In use, when applying current to the coils, magnetic driving forces between the magnets and the coils are generated, therefore a lens can be held in the moving unit and driven to move along with the moving unit for focusing. However, if the size of base is slightly less than the designed size, it will result in the side plates not being clamped securely to the base, or when the size of base is slightly greater than the designed size, it will result in the side plates deforming.
Therefore, it is desirable to provide a voice coil motor and a manufacturing method for the voice coil motor which can overcome the above-mentioned problems.